Ancient Viruses Are Buried in Your DNA

Posted on by Lori Jia

The New York Times, October 4, 2017

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In July, scientists reported that a strange protein courses through the veins of pregnant women. No one is sure what it’s there for.

What makes this protein, called Hemo, so unusual is that it’s not made by the mother. Instead, it is made in her fetus and in the placenta, by a gene that originally came from a virus that infected our mammalian ancestors more than 100 million years ago.

Hemo is not the only protein with such an alien origin: Our DNA contains roughly 100,000 pieces of viral DNA. Continue reading “Ancient Viruses Are Buried in Your DNA” →

Friday’s Elk, September 24, 2017

Posted on by Matt Kristoffersen

In the field of ancient DNA, scientists keep doing the impossible. The very idea of reading genes from organisms that died thousands of years ago once seemed absurd. Then it became fairly commonplace. Still, some kinds of old DNA seemed off limits. The only place scientists could hope to find it was cold places where the molecule had a chance of surviving for millennia. Finding ancient DNA in a place like Africa seemed a fool’s errand.

Scientists are crashing through that barrier, too. A place like Africa may not be as cold as Alaska. But it does include sites–high-altitude caves, for example–where some DNA can survive. And new, sensitive tests can detect DNA in samples that would have seemed gene-free a few years ago. Continue reading “Friday’s Elk, September 24, 2017” →

Clues to Africa’s Mysterious Past Found in Ancient Skeletons

Posted on by Lori Jia

The New York Times, September 21, 2017

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It was only two years ago that researchers found the first ancient human genome in Africa: a skeleton in a cave in Ethiopia yielded DNA that turned out to be 4,500 years old.

On Thursday, an international team of scientists reported that they had recovered far older genes from bone fragments in Malawi dating back 8,100 years. The researchers also retrieved DNA from 15 other ancient people in eastern and southern Africa, and compared the genes to those of living Africans.

Their analysis, published in the journal Cell, reveals important clues to Africa’s mysterious prehistory, including details of massive migrations that shaped the populations we know today.

Continue reading “Clues to Africa’s Mysterious Past Found in Ancient Skeletons” →

Friday’s Elk, September 16, 2017

Posted on by Matt Kristoffersen

This week I asked my editor at the New York Times if I needed to make a disclosure of possible conflict of interest. The trouble is that I have a tapeworm named after me: Acanthobothrium zimmeri.

The reason for the question was the topic of my column: the dire threat that parasites now face. A massive study of parasites around the world shows that climate change could drive as many as 1 in 3 species extinct. I worry that Acanthobothrium zimmeri, which infects a tropical skate, will wink out of existence. My editor didn’t see the need for a disclosure. But I figured that you, dear reader, should know. Continue reading “Friday’s Elk, September 16, 2017” →

Climate Change Threatens the World’s Parasites (That’s Not Good)

Posted on by Lori Jia

The New York Times, September 13, 2017

Link

Animals around the world are on the move. So are their parasites.

Recently, scientists carried out the first large-scale study of what climate change may do to the world’s much-loathed parasites. The team came to a startling conclusion: as many as one in three parasite species may face extinction in the next century.

As global warming raises the planet’s temperature, the researchers found, many species will lose territory in which to survive. Some of their hosts will be lost, too.

Continue reading “Climate Change Threatens the World’s Parasites (That’s Not Good)” →